The Value Of Transthoracic Contrast Echocardiography Combines Contrast-Enhanced Transcranial Doppler To Screening Patent Foramen Ovale

Objective: Patent Foramen Ovale(PFO) is closely associated with cryptogenicischemia stroke, Especially in young patients.It is as the paradoxical embolism fromvenous circulation channel,Leading to cerebral infarction. The relationship betweenpatent foramen ovale and cryptogenic stroke increasingly attracted the attention ofclinicians. It is important to how to choose a non-invasive and easy inspectiontechniques to make an accurate diagnosis for PFO patients. Transesophagealechocardiography（TEE） is currently is considered as the gold standard of diagnosis ofPFO in clinical. But its invasive, depends on the patients’ ability to swallow is itsunavoidable shortcomings. Simple transthoracic echocardiography (TTE) andcontrast-enhanced transcranial transcranial Doppler (c-TCD) for checking the patentforamen ovale have their own strengths and weaknesses, the former owes highspecificity but relatively poor sensitivity, Particularly affected by the restrictions of thepatients’ thorax and pulmonary gas interference; The latter is currently in clinicalwidely used because of its high sensitivity, But it can not probe the intracardiacstructures,and it is unable to distinguish the extracardiac channel for the right-to-leftshunt,it is an indirect ways of checking PFO.The technique of TTE combined withc-TCD to exam to check of patent foramen ovale, has the advantages non-invasive,simple, repeatable and easily to be accepted by patients. In our study, We apply the jointapproach to PFO screening studies of ischemic stroke patients,and comparisonof TEE’sresults.We will summarize the application of the joint technical study PFO detectionrate, And to investigate its clinical value.Method: We applied transthoracic contrast echocardiography combined c-TCDstudy of41inpatients who were highly suspected PFO because their cryptogenicstroke,migraine, TIA symptoms. All patients underwent TTE contrast echocardiography joint c-TCD.They underwent conventional transthoracic echocardiography andtranscranial Doppler before the Joint Inspection. During transthoracic echocardiography,the Sonographer observed the general structure of the heart, they determined whetherpatients have abnormal structure or not,such as abnormal cardiac shunt and atrial septalaneurysm.During the process of transcranial Doppler,the doctor First to found asuitable location in the bilateral temporal window, then observed bilateral middlecerebral artery blood flow velocity, the abnormal audio signal and spectrum. WhetherThey were normal or not. Then These patients underwent injecting agitated saline by thethe antecubital intravenous,and soon later underwent the transthoracicechocardiography(TTE) and transcranial Doppler ultrasonography(c-TCD)simultaneously.The doctor would record the number of PFO positive patientsat the same time and the respectively when the examination results were negative, itwould checking again with the Standard Valsalva maneuver.All test results forPFO-positive patients were subsequently implemented TEE examination under doctor’sadvice, thses test results for PFO-positive patients were voluntary implemented TEEexamination to confirme the presence of PFO. We made TEE as the referencestandard,analyze the results of TTE contrast echocardiography, c-TCD,the joint ofc-TTE and c-TCD.Result：During41inpatients with cryptogenic stroke,migraine, TIA, we screened32PFO positive patients Through the joint inspection of TTE contrastechocardiography and c-TCD. And then32PFO had been diagnosised by TEE，9negative patients,and then had been diagnosised1for PFO positive patient by TEE，therest were9true-negative patients, In contrast to TEE, TTE contrast echocardiographyinspected PFO29true-positive,4False-negative,8true–negative, c-TCD inspectedPFO30true-positive,3False-negative,8true–negative,Both of them had no falseposition. We made TEE as the reference standard, the detection rate of c-TTE、c-TCD、the joint of c-TTE and c-TCD were87.9%、90.9%、97.0%，Specificity were100%,In thedetection of patent foramen ovale the joint of c-TTE and c-TCD and TEE had a goodconsistency.Conclusions: The joint of c-TTE and c-TCD can effectively improve the detectionrate of patent foramen ovale,it can make precise diagnosis in PFO. Compare withsimple transthoracic echocardiography (TTE) or contrast-enhanced transcranialtranscranial Doppler, The detection rate was increased, it has such advantages assimple, non-invasive, repeatable, easily to received by patients, It may be screening out the vast majority of PFO patients. It can be used as a suitable screened PFO promotionInspection techniques.it can Provide a clear cause For patients,and can Provide accurateinformation to clinicians to develop the next treatment. It is Of great significance.